Sir Edward Bullard made important contributions to every branch of twentieth-century geophysics. He studied under Ernest Rutherford at Cambridge, and conducted some of the first serious investigations of marine geology, showing sediment wedged in thick patches under the continental shelf, and measuring heat flow from the planet's interior. During World War II he worked on anti-mine technology, installing current-carrying wires inside the hulls of allied ships, which greatly reduced the ships' susceptibility to magnetic mines.

His 1967 study established that the shorelines of Western Europe and America were almost perfectly matched to a depth of 500 fathoms, and he then showed that radioactively-dated rocks from coastal African regions matched similar rocks in South America -- supporting Alfred Wegener's theory of continental drift. Working with Walter M. Elasser, he developed a theory to explain the origin of the Earth's magnetic field, and he later led the team that developed potassium-argon dating, used for determining the age of materials too young for the uranium technique and too old for carbon-14 dating. He was almost universally called Teddy, and Sir Teddy after being knighted.